Paleoecology

Paleoecology is the study of fossil organisms and their relationship to
ancient environments. Paleoecology falls under the broader category of
paleontology (the study of fossils). A person who studies and investigates
paleoecology is called a paleoecologist. The study of paleoecology is
important to scientists because it reveals so much about such natural
aspects of ancient history as wind conditions, climates, temperatures, and
ocean activity. Critical to the field of paleoecology is the intense
concentration of chemicals found in fossils; such chemical data reveals
much information about the world of long, long ago.

The field of paleoecology was developed by American geologist (a person
who studies the history of Earth) Kirk Bryan (1888–1950). Bryan
focused his investigations on weather changes from the past by using
information from ancient soils and pollen. His work gathered enough
interest from the scientific community to help develop the field of
paleoecology.

Paleoecologists can find clues about the ancient environment and the
organisms that lived during a particular time on Earth by examining fossil
organisms, the different varieties of those fossils, and the sediment in
which they were found. Sediment is made up of rock particles, minerals,
and fossil organisms that, due to the forces of weather and time, have
deposited on top of each other, forming layers. These layers compress and
harden, forming sedimentary rock.

Sediment also collects at the bottom of an estuary (area of water where
the sea meets a river). Each layer of sediment represents a piece of time
in history. Paleoecologists take core samples of the sediment—by
pushing a tube down into the estuary and pulling out a sample of the
muddy bottom—that provide a historical record of the past. Material
found closest to the top of the tube is the youngest sediment; material
near the bottom of the tube sample is the oldest. (The idea of sediment
layers is similar to that of tree rings, which reveal the age of a tree.)

For example, marine (sea-dwelling) fossils have a significant accumulation
of chemicals in their skeletons. By studying these chemicals,
paleoecologists can draw conclusions about what was happening in the
environment and what was living in the areas surrounding oceans. Because

A Devonian plant fossil.
(Reproduced by permission of the

Corbis Corporation [Bellevue]

.)

of what is recorded in fossils found in water environments,
paleoecologists most frequently study these types of fossils.

Words to Know

Fossils:
The remains, traces, or impressions of living organisms that inhabited
Earth more than ten thousand years ago.

Paleontology:
The scientific study of the life of past geological periods as known
from fossil remains.

Sediment:
Sand, silt, clay, rock, gravel, mud, or other matter that has been
transported by flowing water.

Sedimentary rock:
Rock formed from compressed and solidified layers of organic or
inorganic matter.